The Avengers: Doomsday Trailer Reveals One Fight Marvel Fans Never Thought They'd See

The first trailer for "Avengers: Doomsday" is finally here, revealing Robert Downey Jr.'s Doctor Doom voice, a first look at the Fantastic Four interacting with The Avengers, and much more. It's also become clear that the fifth "Avengers" movie is likely going to be an "Avengers vs. X-Men" film, judging by the many brief shots in the trailer of mutants fighting the known heroes of the Marvel Cinematic Universe.

Among the related battles glimpsed here are Mystique (Rebecca Romijn) shapeshifting into Yelena Belova (Florence Pugh) from the New Avengers and Cyclops (James Marsden) shooting his eye laser at a group of people. In addition, we may yet get to see Magneto (Ian McKellen) take on Thor (Chris Hemsworth) in the film itself. Indeed, these kinds of showdowns between fan-favorite characters can only happen in an established franchise like the MCU.

What's more, "Avengers: Doomsday" will even include a fight that Marvel fans never thought they'd see. Not because it was impossible or would require a lot of build-up. Rather, it's because it's a tussle between two seemingly random characters that no one expected to duke it out.

We're referring, of course, to Channing Tatum's Gambit fighting Simu Liu's Shang-Chi.

It's been five years since the release of Shang-Chi's solo movie, "Shang-Chi and the Legend of the Ten Rings," which was previously the only time we'd seen him in the MCU outside of the animated shows "What If...?" and "Marvel Zombies." So, given that it's unclear if "Shang-Chi 2" is ever going to happen, merely seeing the character again in live-action would've been surprising enough. Likewise, Tatum's Gambit has gone through a lot, with his solo movie having been stuck in development hell for over a decade. Hence, the two squaring off in "Doomsday" is both bizarre and cool.

Having this serve as our reintroduction to Shang-Chi in the MCU is kind of shocking. Certainly, no one would have had this match-up on their bingo card, as neither Shang-Chi nor Gambit have previously gotten their proper due on the big screen (much less in an important, universe-wide crossover event like this). Yes, Shang-Chi's solo movie was a hit in 2021 despite theaters barely being functional after the COVID-19 lockdowns when it arrived, but again, he's been mostly ignored since then. Meanwhile, Gambit became a highlight in 2024's "Deadpool & Wolverine" despite never getting a solo movie. The point being, these characters work, and while their pairing here is far from obvious, it's worth getting excited about.

After all, with the MCU being as big as it is, it's easy to pair characters from very different corners of the franchise. Case in point: One of the best parts of "Avengers: Infinity War" was getting to see Bucky Barnes, aka. Winter Soldier (Sebastian Stan), pick up Rocket Raccoon (Bradley Cooper) and spin him around as Rocket reigns fire down upon Thanos' army in the film's climax. It's a brief moment, but the sight of a super serious, grounded character like Bucky interacting with a clownish alien like Rocket is hilarious, and it leads to a fantastic joke involving Rocket desperately wanting to steal Bucky's metal arm.

Suffice it to say, with "Avengers: Doomsday" bringing the X-Men fully into the MCU, we're about to see some wild character interactions. Perhaps Joseph Quinn's Human Torch will chat with Alan Cumming's Nightcrawler. Or imagine if Ian McKellen's Magneto winds up talking to David Harbour's Red Guardian?! We'll see if these and other like them come to pass when "Doomsday" hits theaters on December 18, 2026.